This invention relates to solenoid constructions, and in particular, to a low cost solenoid having improved operating characteristics. While the invention is described in particular detail with respect to certain preferred applications of the solenoid, those skilled in the art will recognize the wider applicability of the inventive principles disclosed hereinafter.
A conventional solenoid is designed so that magnetic force is exerted across an air gap generally perpendicular to the pole pieces in such a manner as to close the gap. Latching solenoids also are well known in this device, wherein a plunger moves from its first to second position. The plunger is maintained in the second position until a physical force is exerted on the plunger to return it to its initial starting position.
We have determined that a relatively efficient, and low cost solenoid construction can be obtained by utilizing in its simplest form, a freely moveable permanent magnet which operates between first and second pole pieces to operate the solenoid in a unique fashion. In this construction, a divider separates the first and second pole pieces.